diff --git a/apps/dav/lib/CalDAV/CalendarObject.php b/apps/dav/lib/CalDAV/CalendarObject.php
index 32bcff900c222..b9c7f3086d597 100644
--- a/apps/dav/lib/CalDAV/CalendarObject.php
+++ b/apps/dav/lib/CalDAV/CalendarObject.php
@@ -116,9 +116,13 @@ private function createConfidentialObject(Component\VCalendar $vObject) {
 					case 'CREATED':
 					case 'DTSTART':
 					case 'RRULE':
+					case 'RECURRENCE-ID':
+					case 'RDATE':
 					case 'DURATION':
 					case 'DTEND':
 					case 'CLASS':
+					case 'EXRULE':
+					case 'EXDATE':
 					case 'UID':
 						break;
 					case 'SUMMARY':